Automatic tuning device



June 11, 1935. R, L HEEREN 2,004,324

AUTOMATIC TUNING DEVICE Filed Feb. 25, 1931 2 Sheets-Sheet 1 INVENTORMMB.5QWW

%#M v akm ATTORNEY AUTOMATIC TUNING DEVI GE Filed Feb. 25, 1931 2Sheets-Sheet 2 ATTORNEY Patented June 11, 1935 UNITED sures PATasrOFFICE My invention relates to an automatic tuning device for radiosets. It is theprincipal object of the present invention to provideautomatic means operated by a 6 clock, for use with radio receivingsets, for tuning in on previously selected stations at previouslyselected times, and which requires no personal attention whatever at thetimes when the tuning operations are'accomplished,

- means operated by a clock for discontinuing radio reception atpreviously selected times, and which requires no personal attentionwhatever at the times when the discontinuing operations areaccomplished.

Other, objects and features of the invention will be pointed out or willbecome apparent upon a reading of the specification.

In the drawings which show, for illustrative aurposes only, a preferredformof the inven- Fig. 1 is a diagrammatic view of an automatic Liningdevice embodying features of my inven- Fig. 2 is a side elevation of atuning condenser showing a station block and a station contactor;

Fig. 3 is an edge elevation of the parts shown in Fig. 2;

Fig. 4 is a plan view of certain Pie.

Fig. 5 is a plan view of a clock, partially broken away to show the timecontactor.

In said illustrative drawings I 0 indicates generally a tuningmechanism, preferably in the parts shown in form of a variablecondenser, the movable plates of whichare mounted on a shaft II. Theshaft II is operated by an electric motor I. In the form shown in thedrawings there is fixed to the shaft I I a worm wheel it, which mesheswith a worm l3. Worm II is fixed to a shaft II, which is operable byhand by turning a dial l5 and which is also operable by the motor It,the armature oi which carries a spur gear II, which meshes with a spurgear I! fixed to the shaft H.

28 represents a clock. One or more switches which are operable by themechanism of the clock are provided for controlling the motor I6, 80. asto cause the motor to move the condenser ll to tune in selected stationsat selected times.

These switches also will operate at selected times to discontinuereception by cutting of! the current from the tube filaments. In theform shown It is a further object to provide automatic- 1 cum. ((31.250-2.

hour hand 3|. Attached to supports "-36 made 0! insulating material andadjacent to the path of the time contactor II are a number of sets oftime contacts 31-38-49. Each set consists of three contacts, which arepositioned so as to contact with the contacts 32-43-34 when thecontactor II is in the proper position. In the drawings I show threesets of these time contacts, the contacts of. the first set beingnumbered 31, 31, 31, the contacts of the second 0 set being numbered 38,a, 38, and the contacts of the third set being numbered 39, 89', 38. Inthe form shown the insulating support 36 carrying the outer contacts ofeach set, viz., 31*, 38, 39, is made in the form of a ring, which ispreferably rotatably adjustable slightly about its center.

One or more switches for stopping the motor it are provided, which areoperable'by the motor when it has moved the condenser Hi to points atwhich selected stations are tuned in. In the form shown irf the drawingsthese switches are the station blocks 2l-22. Rigidly attached to thetuning condenser shalt l I, but insulated thereirom, is a stationcontactor, preferably in the form of a radial arm 19. The stationblocksZl-M are attached to a fixed current conducting support 20 adjacent tothe path of the contactor I 9. These station blocks are adjustable inposition, preferably by providing means, such as screws 23, for clampingthem in any desired position in a circular groove 24 in the support 20.In the form shown each station block comprises a body part 25 made ofinsulating material, to which is connected two contacts 28-21. One ofthese contacts is preferably made of spring material, this being thecontact 21 in the form shown in the drawings. Contact is made betweenthe contacts 28, 21 when the contactor I9 coacts with the spring contact21. In the form shown, one oi the contacts on each station block iselectrically connected to the support 2..

ill-l0 are double pole single throw manually operated tuning switches,and "-4! are single pole single throw manually operated stop switches.All of these switches are mounted preferably on the outside of the radiocabinet, so as to be conveniently accessible. It will usually be mostconvenient to arrange the switches 40 in diflerent rows, each rowcorresponding to a different broadcasting station. 42 is a solenoidswitchin the motor circuit. This switch is normally spring closed unlessheld open by the solenoid.

43 represents generally the main switch, which can be operated manually,or magnetically, by

tacts 3'! is provided for each separate program which it is desired toreceive and for each dis-' continuance of reception during a given cycleof automatic control. For instance, if there are six desirablebroadcasting stations available and each broadcasts a one-hour programevery twelve hours so that there is a one-hour gap between successiveprograms, six station blocks 2! and twelve sets time contacts 37 wouldberequired for providing complete automatic control for receiving all theprograms and discontinuing reception alter each program during thetwelvehour cycle. Generally it is desirable to provide the clock 28 withsets of time contacts 31 which are arranged at hourly or half hourlyintervals.

The number or tuning switches 40 to be provided will be equal to theproduct of the number of station blocks 2i and the maximum number oftimes it-will be desired to tune in during a cycle. The number or stopswitches 48 to be provided will be equal to the maximum number ofdiscontinuances of reception which will be desired during a cycle.

The switches 48 are arranged so that when one is closed one contact ofone or the sets of time contacts 31, 38 or 39 is connected to one side50 or the incoming power circuit, and another contact of the same set oftime contacts is connected to one of the contacts of one of said stationblocks. The third contact of said set of time contacts is connected tothe other side SI of the incoming power circuit through the switch 42and the motor 85. The other contact of said station block is alsoconnected to the side II of the power circuit through the solenoid oi.the switch 82.

The switches 49 are arranged so that when one is closed one contact ofone of the sets of time contacts 31 is connected through the solenoid 45to one side so of the incoming power circuit.

The method of operation of this device is as follows: a

If it is desired to operate the receiving set manually, all the switches40 and ll should be open. The switch 43 should be closed and the desiredstation should be selected by means of the tuning dial It. To stopreceiving, open switch 83.

If automatic operation is desired; all the switches 40 and M are firstopened. The condenser lll is then set by means of the tuning dial l soas to tune in a given station at a given time. A station block 2! isthen set so that the contactor l9 makes contact between the contacts 28and 21. Other station blocks are similarly set to correspend to suchother stations as it may be desired to receive from. The set is thenconnected to a source of electrical energy. Care should be taken to seethat the condenser i0 is free to revolve continuously in one direction.The proper tuning switches in and stop switches ii are then closed toprovide for the automatic reception of the desired programs at thedesired times.

For example, let us assume that it is desired to tune in automaticallyat 3 P. M. on the station represented by station block 22 and to stopthe set at 4 P. M. Any time within twelve hours prior to 3 P. M., thetuning switch 40 and the stop switch 4i, which are, shown closed in Fig.1, may be closed, and the receiving set is then set for the desiredautomatic operation. At 3 P. M., the time contactor 3| will be in theposition shown in Fig. 1, and the interconnected contacts 32, 33 and 34will make contact with the time contacts 38 38 and 38, respectively.Current will flow from line wire 50 through solenoid M, closed switch40, contact 38*, contact 33, contact 34, contact 38", switch 42, motor6, to line wire 5|. The flow of current through the solenoid 44 willclose the switch 83 and light the tube filaments. The flow of currentthrough the motor I6 will operate the motor, which will turn the shaftII and the tuning condenser ill to the position shown in Fig. "1, atwhich position the receiving set will be tuned in on the stationrepresented by the station block 22. When the tuning condenser It hasreached this position, the motor IE will be automatically stopped, aswill now be described. At this position of the condenser ID, the stationcontactor l9 will come into contact with the spring contact 21 of thestation block 22 and will close a circuit through the contacts 26 and Elof this station block. Current will then flow from line wire 50 throughsolenoid 44,

closed switch fill, contact 38, contact 83, contact 32, contact 38closed switch 4d. station block 22, support 20, the solenoid of switch42, to line wire 5!. The flow of current through the solenoid of switch32-. will open the switch and stop the flow of current through the motorIS. The motor it will then stop and the station contactor l9 andcondenser It will remain in the position shown in Fig. 1. By slightlymoving ring 38 angularly about its center adjustment can be made sothat-the contactor 3! will make contact long enough so that current willflow the proper length of'time to operate the circuit but will be cutoil shortly after operation is complete. When the contactor 3i driven bythe mechanism of clock 28 leaves contact set 38 the circuit through thesolenoid of the switch 42 which has Just been de-' scribed will bebroken, allowing the switch S2 to close. The motor I 6 will not operateagain atthis time, however, because the motor circuit has also beenbroken by the movement of the time contactor away from contact set 38.

When 4 P. M. arrives the contacts on the time contactor 3! will contactwith contact set 31. Current will flow from line wire 50 through contact 47, solenoid 45, closed stop switch 4! contact 31, contact 32,contact 3, contact 31, switch 42, motor i8, to line wire 5|. The flow ofcurrent through solenoid 45 will open the switch 48 and cut on thecurrent from the tube filaments, thereby effecting a discontinuance ofradio reception. The opening or the switch 48 will open the contact Mand stop the flow or current through the motor !6.

Similarly, by closing several 0! the switches 4| corresponding todiflerent times and diil'erent stations, a consolidated program made upfrom the programs from several stations can be. ar-

ranged in advance andv played automatically at the proper times withoutthe necessity of givingany personal attention to tuning in at the timeswhen the tuning operations are accomplished. 1

Unless the tuning switches 40 are opened after the end or the cycle, thesame tuning operations tacts, each set including three contacts, andhaving a contactor operated by said clock mechanism for interconnectingthe contacts of any one or said sets, a plurality of timing switches,each of said tuning switches connecting one of said contacts to theother side of the incoming power circuit and connecting another contact01' the same set oi contacts to said first mentioned switch, the'thirdcontact of the same set of contacts being connected to said one side ofthe in- 10 coming power circuit through said motor.

REINHARD L. HIEEREN.

